Edward c



E. C. WOOD.

RECEIVER MOUNTING FOR SUBMARINE SIGNALS.

APPLICATION FILED MAY 1.8., I.9I8

menwaApr. 13,1920.

2 SHEETS-SHEET 1.

Patented Apr. 13, 1920.. r

2 SHEETS-SHEET 2.

nHQMI "UNTTED sTnTns PATENT OFFICE.

EDWARD C. WOOD, OF SOMERVILLE, MASSACHUSETTS, ASSIGNOR TO SUBMARINESIGNAL COMPANY, OF PORTLAND, MAINE, A CORPORATION OF MAINE.

I RECEIVER-MOUNTING- FOR SUBMARINE SIGNALS.

Application filed May 18, 1918.

To aZZ whom t may concern:

Be it known that I, EDWARD C. WOOD, of

Somerville, in the county of Middlesex and State of Massachusetts, acitizen of the United States, have invented a new and useful Improvementin Receiver-Mountings for Submarine Signals, of which the follow ing isa specification.

A microphone installed on board ship to receive signals or sounds issubject not only to the influence of those sound waves approaching itfrom outside the ship but also to vibrations originating on shipboard.Thus at the receiving station, say the pilot house, there is apt to beconfusion between those sounds which it is intended to receive and thosewhich may be called immaterial., f. c., those which, originating at thereceiving station, convey no intelligence to the observer. He is intenton analyzing or receiving sounds or signals from a distance and his workis confused by sounds otherwise originating.

I shall describe my inventionl with relation to shipboard installation,but I do not mean to limit it thereto as it may be otherwise used. Itrelates to a mounting of a microphone, such that not only are theundesirable lateral vibrations largely eliminated, but the microphonevibrations are amplified.

My invention will be understood by reference to the drawings in which itis shown in its preferred form;

Figure l being a horizontal section of a mechanism embodying myinvention, and

Fig. 2 a section on line 2 2 of Fig. l.

A is a plate which may be part of the skin of the ship, preferably aportion of the side thereof, A1 being the usual ribs. B a heavy metallicinertia ring which is bolted to the ribs by bolts b. It may be otherwiseor additionally attached if thought best. C is a heavy cast iron ringcarrying supports c for knife edges Z or the like projecting laterallyfrom a reed or other vibrator D. Hence it is convenient to call the ringC an anvil. The supports c, c are preferably threaded and screw into theanvil so as to be adjustable. Between the anvil Specification of LettersPatent.

Patented Apr. 13, 1920.

semi No. 235,377.

C and the ring B is a gasket E preferably a soft rubber ring of suchsize and character as to serve as an acoustic insulator between the twoparts and so reduce to a minimum the communication of vibrations betweenB, which is attached to the ship, and the parts attached to C as well asC itself. The supports may be flat on their upper surface as shown inone instance or may be grooved as at 01 or otherwise as thought best.

TWhen the apparatus is in position the reed or its equivalent D isattached to the plate A by a wire F, preferably by a screw eye a whichis held in place by a set nut al, the upper end of the wire beingattached to a second screw eye Z1 having a somewhat longer shank, whichis held in place by set nuts (Z2, (Z2, the whole being arranged to holdthe knife edges Z firmly on their seats so that the reed will vibrate inphase with the plate A.

The upper end of the screw eye Z1 holds a core, preferably in the formof a cup, Gr which as shown is threaded to it and rests against theupper nut Z2 so that it also vibrates with the reed D, and around thiscup, which is preferably made of aluminium, is wound a coil H ofinsulated wire the ends of which are connected with binding posts itwhich in turn are connected by wires h1 with a source H1 of directcurrent.

The binding posts /L are mounted in an inverted U-shaped strap J whichis attached by screws j to the anvil C, said binding posts beinginsulated from the strap J by sleeves and washers jl of insulatingmaterial.

To the strap J is also attached, though insulated therefrom, one memberK Vof the microphone, the other member K1 of which is attached by thescrews Z to a plate L which forms the end of a copper tube'Ll which isof slightly smaller diameter than the cup G so that it may vibratefreely within it, and which forms a secondary to the coil H. The leadsZo of the microphone are connected to a telephone receiver or otherindicator and a source of current in the usual manner. M is a coverbolted to the ring B with a rubber gasket in it to make it watertight.

. In practice compressional waves actuate the plate A and its vibrationactuates the reed D which is preferably tuned, and the cup G, and setsin vibration the coil H through the instrumentality of the cup G aroundwhich the coil H is tightly wound.

The coil H produces a magnetic flux which acts uponthe copper tube L1causing it to vibrate and energize the microphone.

The instrument should be highly eiiicient as it will not be aiected bylateral vibrations or any other vibrations than those substantiallynormal to the plate A, but to this end the attachment should beabsolutely rigid. While the etliciency of the couple between H and K1may be low, there is a considerable gain in the couples between A and Dand hence the eiiiciency of the apparatus as a whole will give extremelygood results.

It is believed that an apparatus of this character is absolutely new andhence l do not mean to connue myself to the exact embodiment of myinvention shown in the drawings and above described.

liVha't 1 claim as my invention is:--

l. The indicator mounting above described comprising a compressionalwave-receivino` member, a vibrating member connected thereto, anindicator, a transformer one member of which is connected to saidvibrating member, the other member being mounted to vibrate andconnected to said indicator, and connections whereby one member of saidtransformer may be electrically energized.

2. The microphone mounting above described comprising a compressionalwave receiving member, a vibrating memberconnected thereto andacoustically insulated therefrom, a direct current circuit operativelymounted on said vibrating member and comprising a coil, a secondarymounted to vibrate located within said coil, and a microphone and itsconnections, one member of said microphone being mechanically connectedto said secondary to vibrate therewith. Y

3. The microphone mounting above described comprising a compressionalwave receiving member, a vibrating member connected thereto, a coremounted on said vibrating member, a coil wound around said core andforming part of a direct current circuit, a secondary mounted to vibratelocated within said coil, and a microphone and its connections, onemember of said microphone being mechanically connected to said secondaryto vibrate therewith.

Y 4l. The microphone mounting above described comprising a compressionalwave receiving member, a vibrating member connected thereto, a core ofmagnetic material mounted on said vibrating member, a coil forming partof a direct current circuit and` adapted to move with said core, asecondary mounted to vibrate located within said coil, and a microphoneand its connections, one member of said microphone being mechanicallyconnected to said secondary to vibrate therewith.

5. T he microphone mounting above described comprising a compressionalwave receiving member, a vibrating member connected thereto andacoustically insulated therefrom, a core mounted on said vibratingmounted on said vibrating member, a coil forming part of a directcurrent circuit and adapted to move'with said core, a secondary mountedto vibrate located within said coil,

land a microphone and its connections, one

member of said microphone being mechanically connected to said secondaryto vibrateV therewith.

7. ln a device of the kind described, a compressional wave receivingmember, a vibrating member and a microphone one member of which isconnected to said vibrating member, and means for connecting saidreceiving member and said vibrating member comprising an anvil, anacoustic insulator located between said anvil andsaid receiving member,said anvil beingV provided with means to support said vibrating memberat nodal points and said vibrating member being attached to saidreceiving member to be vibrated thereby.

8. In a device of the kind described, a compressional wave receivingmember, a vibrating member and a microphone one member of which isconnected to said vibrating member, and means for connecting saidreceiving member and said vibrating member comprising an anvil, anacoustic insulator located between said anvil and said receiving member,said anvil being provided with n'leans to support said vibrating memberat nodal points and saidvibrating member-being attachedfto saidreceiving member to be vibrated thereby, said anvil and said receivingmember being acoustically insulated vfrom each other.

A microphone mounting comprising a receiving member, an inertia memberconnected thereto, an anvil, means located between said anvil and saidinertia member whereby the vibrations of said inertia member will beinsulated from said anvil, and a microphone one member of which isconnccted to said receiving member and said anvil.

l0. That method of receiving at an indicator compressional Waves comingfrom a desired direction, which consists in causing one member of atransformer to be vibrated by said Waves in a line parallel With saiddirection, whereby the electrical energy due to the transformer actionmay be collected on an indicator, and absorbing the vibral0 tions orother compressional Waves before they reach the transformer.

EDWARD C. WOOD.

